[dorkbotdc-blabber] SmarTrip Apparel

[Nikolas Coukouma]

On Tue, Jul 22, 2008 at 10:41 AM, Tom Lee <thomas.j.lee at gmail.com> wrote:
> Hey Q, I left a comment on your HacDC post but I thought I might as well
> pipe up here, too, in case there's some other folks on this list who can
> fill in the gaping holes in my RFID knowledge.
>
> The only other data points I have to share from my initial SmarTrip
> dissection are these: I removed the chip and hooked it up to some
> (nonstranded) speaker wire wrapped into a loop of the same approximate
> length as the ST's internal antenna, and it worked like a champ -- range was
> improved, if anything.  I could get the farecard machines to notice it from
> several feet away.
>
> I then attempted to reconfigure the device into something slightly less
> horrible. I took the same length of wire -- magnet wire this time -- wrapped
> it into an attractive loop, used heatshrink tubing to seal it all up, and
> mentally prepared myself for having another item on my keychain.  Then...
> nothing.  The thing still worked, but very intermittently, and range was
> terrible.  It wasn't really usable.
>
> I have to admit, I'm at a loss as to what the problem was.  The speaker wire
> was a larger gauge, but surely the magnet wire was more capable than the
> disgusting printed antenna used in the original ST.  I've chalked it up to
> "antennas are complicated" and ignored it, though -- hopefully you guys will
> have more luck.

I'm interested in this project ...
I'm also lacking in sewing skill, although I do have machine. What I
do have is a bit of experience with antenna design (and broadcast
engineer as a father to discuss with).  I'm wondering if the problem
is that there's an induction coil element to this, since the chip
draws power from that (yes?).

Cheers,
-Nikolas


> On 7/22/08, Andrew Q Righter <andrew at i11industries.com> wrote:
>>
>> All,
>>
>>      I am putting out a call for anyone familiar with sewing conductive
>> thread (or that thinks that they could do it) that may want to work on a
>> project with me to create a piece of clothing with an embedded smarTrip
>> micro controller. Nothing amazing and it's probably already been done but I
>> think it'll be cool to have :D
>>
>> Shoot me some mails off-list. Hopefully you'll have a sewing machine,
>> 'cause I don't.
>>
>> Cheers,
>>
>> --
>> Andrew 'Q' Righter
>>
>> Founder of the Q labs
>> Co-Founder of HacDC
>>
>>
>> [856] 625-4253
>> andrew at i11industries.com
>>
>> ........................................................................
>> .......dorkbot dc: people doing strange things with electricity.........
>> ................... http://dorkbot.org/dorkbotdc .......................
>> ........................................................................
>
>
> ........................................................................
> .......dorkbot dc: people doing strange things with electricity.........
> ................... http://dorkbot.org/dorkbotdc .......................
> ........................................................................
>